HOW TO KNOW THE BUTTERFLIES under sides of the wings are marked and marbled with beautiful and intricate patterns in browns that vary from reddish to seal, and in grays of all shades ; and each hind wing bears wrought in shining silver an " initial" which characterizes the species. In flight all these butterflies follow a zigzag course, so swiftly that the eye can scarcely follow them. They frequent woodsy paths and roads and are likely to alight on the trunk of a tree or on the ground and close their wings, the variegated browns of the under sur¬ face rendering them almost invisible. The cater¬ pillars are spiny, and the head is sometimes adorned with a pair of thorny spines. The chrys¬ alids are angular, usually the color of dead leaves, and are made inconspicuous by both colors and pattern. The Violet-tip Polygonia interrogationis (Pol-y-go'ni-a in-ter-ro-ga-ti-o'nis) Plate XXIII, Fig. i, 2, 4, 6 This species differs from its allies found in the East by the presence of a black spot on the upper surface near the base of cell Mj of the front wings, a short distance from the black bar on the discal vein, and opposite the spot in cell M,; and in the form of the silvery mark on the lower surface of the hind wings, which consists of a dot and crescent, resembling 134